The agency said that necessary precautions should be taken during construction, use or inspection of conveyances, which it outlines to include buckets, cages, platforms, skips, or any other shaft-based personnel transport device.
"Personnel riding in conveyances should wear a full body harness with a short, shock-absorbing lanyard, and be properly tied off to a designated attachment point," MSHA said.
"Additionally, when personnel are riding in conveyances, no ropes, chains, slings or lanyards should be attached to, or otherwise hang from, the underside or the outside of the conveyance [as] any of these items could inadvertently foul or tip the conveyance causing persons or material to fall into the shaft."
The agency also reminded operators and contractors to ensure the devices can move and travel in the shaft without tipping or running abnormally, and that riders can safely load and unload on a loading platform when the system is suspended over or within a shaft.
To help prevent further accidents and fatalities, MSHA said it requires "designated attachment points" for safety lanyards.
"The location of the attachment point should be carefully selected to prevent the lanyard from getting snagged or entangled when the conveyance is moving," MSHA said, adding that workers should check themselves and others to confirm everyone is tied off and secure before moving.
The impetus for the PIB stems from a triple fatality earlier this year at an Indiana mine when workers fell more than 500ft from a bucket being lowered down a shaft. None were tied off at the time, the agency confirmed.
